Subj : MESO: Nws Weather Prediction Center College Park Md To : wx-storm@lists.illinois.edu From : COD Weather Processor Date : Thu Jul 17 2025 04:52:04 AWUS01 KWNH 170450 FFGMPD MOZ000-IAZ000-KSZ000-NEZ000-171000- Mesoscale Precipitation Discussion 0721 NWS Weather Prediction Center College Park MD 1249 AM EDT Thu Jul 17 2025 Areas affected...Southeast NEB...Northeast KS...Northwest MO... Concerning...Heavy rainfall...Flash flooding possible Valid 170450Z - 171000Z SUMMARY...Elevated training convection within 850-700mb WAA confluent stream. Incidents of training/repeating likely to result in enhanced totals of 2-3" and possible localized flash flooding. DISCUSSION...Regional RADAR mosaic and 10.3um EIR GOES-E loop shows a weakly anticyclonic arc of increasing thunderstorm activity along the central KS/NEB border extending into northwest MO along/north of stronger surface/boundary layer rooted convection. CIRA LPW animation shows sfc to 700mb layers with confluent enhancement of moisture across the axis added from the northern stream along the trailing edge of the strong exiting northern stream strung across the Upper MS River Valley. This aligns with strong 850mb flux from the south across KS before veering southwesterly into the 700mb layer. Low level flow has strengthened and further veered along/ahead of strong 'ridge-riding' shortwave emerging out of Colorado. The connection of streams have provided solid WAA and 925-700 frontogenesis across western KS through the activating arc. Convection is utilizing the edge of slightly steepened lapse rates and the northern gradient of MUCAPE that tightly packs from 500-1500 J/kg in the area of WAA ascent. Combine with the deeply confluent moisture streams, provides solid moisture flux and ample deep layer moisture of 1.75-2". So even though cells are elevated, moist lower levels will not result in much sub-cloud evaporation keeping rainfall efficiency relatively high. Limited capping, resulted in large area of over-turning, so individual updrafts are competing to broaden/merge with other ascent parcels. This is resulting in broader area of 1.5"/hr rates though spots up to 2"/hr becoming likely. Deep layer steering from 700-400mb is generally parallel to the boundary and the 500-1000mb thickness ridge is south enough that propagation vectors are also aligning favorably for spots of training/repeating to occur. Spots of 2-3" are likely to occur with perhaps an isolated small areal coverage of 4" not withstanding. Moderate rainfall from prior day or so, locally reduced FFG values across the NEB/KS into NW MO where 1hr values are 1-1.75"/hr and 1.5-2.5"/3hrs. As such, an incident or two of flash flooding will be possible before instability is exhausted and cells start propagating southward into higher FFG/drier soil conditions. Gallina ....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!= DZ3fjg!9tfGUUxpoxAplG2OfqHfvpUrqIA8ozGFNPBcN3vD8dq-uUBrR3uP0YWlUkejikm3ZfDt= _RTS9WiZeI6vRm7hzD4kco8$ for graphic product... ATTN...WFO...EAX...GID...OAX...TOP... ATTN...RFC...KRF...MSR...NWC... LAT...LON 40599569 40459382 40269278 39749239 39379287=20 39429525 39409714 39179922 39659952 40289806=20 40549692=20 =3D =3D =3D To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM. --- SBBSecho 3.28-Linux * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105) .